Has anyone experience keeping or breeding this species? Almost all the available references state that it’s an aggressively territorial cave-spawner but I remember having them in at the shop once or twice and the males didn’t really seem to bother one another.

I’ve kept it for a short period (couple of months) but never bred it. Never experienced any aggression and they ate just about anything, including brine shrimp nauplii (which was quite funny considering the size of their mouths). They will also eat small fish at night, or at least they only disappeared at night. They usually just stand in one place all day long, pretty much. Mike Noren wrote an article about breeding them on his old website (which has been offline for a couple of years but he might still have the article).

I also seem to recall that Heiko Bleher has stated that Crenuchus spilurus has an infrared organ that they use at night?